turtleFSI: several solids


I am trying to play with turtleFSI with two different solids and a fluid. I created the geometry with a cad software and the mesh with gmsh.

fluid id is 10
solid_1 id is 11
solid_2 id is 12

I am a bit confused since, with only solid_1, it is enough to define in the default_variable dictionary:
dx_f_id = 10, # ID of marker in the fluid domain
dx_s_id = 11, # ID of marker in the solid domain

But since I have two solids, I am not sure how to deal with dx_s_id (?)

I know there is the dx_s_id_list variable that can be set (and dx_s_id keeps the default value 2):

    dx_f_id = 10,
    dx_s_id_list = [11, 12],

Moreover, turtleFSI allows the possibility to deal with the variable solid_properties:

            "dx_s_id": 11,   # solid_1
            "dx_s_id": 12,   # solid_2

It is a bit confusing to me, so if anyone has any knowledge about this, it would be so great ^^

Thank you in advance,


Could you please post this question to issues in turtleFSI as this is more related to turtleFSI rather than general FEniCS feature. It is also easy for us to track all the issues associated with turtleFSI

Also, when you post your issue in turtleFSI, please add error message you get or the problem file that you’re trying to run. To me, it is not clear what the problem is. Your understanding of using several solid regions seems correct.

There was a question about mutil-solid regions recently and that might help you.


Hi Key,

Thank you for your reply. I will post future issues there ^^

For information, I just checked my solid.py and domain.py files and … they are clearly not the same (old installation with conda), which, I hope, will be the only problem to solve!


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